That's what author Steve Siebold found after studying self-made millionaires over the span of three decades. "Getting rich begins with the way you think and what you believe about making money," he writes in "How Rich People Think." In fact, "it wasn't the lack of desire that held the masses back from getting wealthy, but the lack of belief in their own ability to make it happen."

Here are seven mental tricks that rich people use to get ahead, according to Siebold.

They tell themselves there's no shortage of money, even when they don't have enough

If they come up with a great idea they're unable to finance, they "proceed to use other people's money to make it happen," Siebold writes.

"Rich people know not being solvent enough to personally afford something is not relevant. The real question is, 'Is this worth buying, investing in, or pursuing?' If so, the wealthy know money is always available because rich people are always looking for great investments and superior performers to make those investments profitable."

They think of making money as a game

Rich people think of business, life and earning as a game, and "it's a game they love to win," writes Siebold. "This is the reason millionaires still go to work every day chasing their next success. Money to these people is no more than a gauge that tells them when they have achieved their latest target."

Plus, the excitement of "playing the game" pushes them to continually raise their level of expectation, Siebold explains. "The more excited they get, the harder they work and the more they succeed."

They set their expectations unreasonably high

They're up for any challenge, Siebold says: "No one would ever strike it rich and live their dreams without huge expectations. Ancient wisdom says you get what you expect, yet many people decide to limit their lives to middle-class mediocrity in an effort to protect themselves from failure."

They personify money and see it as a friend

Rich people consider money "one of their greatest allies and friends," writes Siebold. "It is a friend that has the power to end sleepless nights of worry, physical pain and can even save their life."

While wealthy people believe money can solve problems and purchase peace of mind, the middle class "sees money as a never-ending necessary evil that must be endured as part of life," he says.

They block out fear

"The great ones are operating at a level of consciousness where fear doesn't exist," Siebold explains. "At this level of thought, anything seems possible. Every dream that seems crazy to the masses looks surprisingly doable."

To operate at this level, you have to be willing to leave your comfort zone, which is exactly what the richest people do, Siebold says. "World class thinkers learn early on that becoming a millionaire isn't easy and the need for comfort can be devastating. They learn to be comfortable while operating in a state of ongoing uncertainty."

They tell themselves that getting rich is natural

The rich believe that "success, fulfillment and happiness are the natural order of existence," Siebold writes. "This single belief drives the great ones to behave in ways that virtually guarantee their success."

On the flip side, the middle class struggles because they expect to: "The masses think they aren't worthy of great wealth. Who am I, they ask themselves, to become a millionaire?"

Instead, ask: "Why not me?" That's what the wealthiest people do, says Siebold.

They tell themselves they deserve to be rich

The wealthy not only believe getting rich is natural, but they believe it's a right.

"World-class thinkers know in a capitalist country they have the right to be rich if they're willing to create massive value for others," Siebold writes.

Meanwhile, the masses think getting rich is reserved for a lucky few. "This distinction in thinking leads the middle class to the lottery and the world class to work," he says. The world class "believe if they make life better or easier for others, it's their right to be rich."

This is an updated version of a story that was previously published in October 2016.